There is an image reading apparatus having a scanner function of reading a document and a transmission function of transmitting image data to information processing apparatus. There is also known an apparatus supporting a plurality of transmission modes in the transmission function. For example, a known image forming apparatus supporting a plurality transmission modes has a transmission function of transmitting image data to a computer, a transmission function of transmitting image data as an attachment file to an e-mail address, and a transmission function of FTP-transmitting image data to an FTP server.